package com.book.service;

import com.book.pojo.User;

public interface userService {
    /**
     * 注册用户
     * @param user
     * @return boolean
     */
    boolean addUser(User user);

    /**
     * 查看用户命是否有效
     * @param username
     * @return boolean
     */

    boolean existUsername(String username);

    /**
     * 登录用户
     * @param user
     * @return User
     */
    User login(User user);

}
